Ocean Creatures
Brown Pelican Pelecanus occidentalis
Survival of the Brown Pelican
We almost lost the brown pelican. According to Pelican Life.org pelicans were threatened by the use of DDT as a pesticide before the 1970's. This pesticide greatly affected the calcium metabolism of pelicans, causing their eggshells to become thinner and more fragile. Their population decreased so dramatically that in 1970, the U.S. Fish and Wildlife Service listed the brown pelican as endangered. As a result, the Environmental Protection Agency banned the use of DDT in the United States and the pelicans began to recover.
Unfortunately, the 2010 Deepwater Horizon oil spill has renewed the threat to the Brown Pelican. When diving beneath the water's surface to find food, the pelicans' feathers become oil-soaked, causing hypothermia and drowning. Pelicans also die by eating oil-tainted fish, which they may also feed to their young. In fact, "just six months ago, brown pelicans had been removed from the endangered species list. Now their recovery could be undermined by millions of gallons of oil in the Gulf." Greg Bluestein and Matthew Brown, Associated Press, May 24, 2010
Also, thoughtless human activity continues to threaten the survival of the brown pelican. These destructive activities are the disturbance of breeding and nesting habitats as well as the abandoning of fishing lines and hooks that later may entangle and injure pelicans.
Description of the Brown Pelican
According to the Monterey Bay Aquarium:
The Brown Pelican is easily recognized by a distinctive large pouch that hangs from the lower half of its long, straight bill. These magnificent birds are gray-brown, with dark wings and white heads with a yellowing crown, yellow eyes, black legs and black, webbed feet.
Most interesting is the pelican’s bill that can hold three times more than its stomach can—nearly three gallons of fish and water. At the end of a successful dive, the pelican drains the water from its pouch and swallows the whole fish, flipping it if necessary, head first.
Brown Pelicans dive for their fish using their keen eyesight and spotting fish from heights of 20 to 60 feet. They dive steeply, with their heads pointed straight down and their wings folded back, plunging into the water. These birds have air sacs under their skin to cushion the blow and to bring them up to the surface.
Usually flying in flocks , their flight pattern may be a straight line or a V-formation, with their powerful wing strokes alternating with short glides. Pelicans often fly close to the water’s surface, seeming to surf the uplift created by the oceans' swells. They are beautiful birds to watch along the coast of San Luis Obispo County.
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